LIPOPROTEIN PROFILING BY HIGH-PERFORMANCE GEL CHROMATOGRAPHY

High performance gel chromatography (HPGC) was used to separate lipopr oteins on the basis of their size and to generate lipoprotein profiles for plasma collected from patients with different lipoprotein phenoty pes. These profiles provided a direct measurement of low density lipop rotein (LDL)-cholesterol which was more precise than LDL-cholesterol v alues calculated by the Friedewald equation. In addition, LDL-choleste rol concentrations were obtained in patients with combined hyperlipide mia in whom LDL-cholesterol could not be accurately calculated by the Friedewald equation. The response of LDL-cholesterol to the drug gemfi brozil was reliably monitored and in addition changes in LDL particle size could be assessed from the LDL apolipoprotein B/cholesterol ratio . HPGC also assisted in the diagnosis of type III hyperlipidemia by re vealing a characteristic lipoprotein profile. HPGC-derived lipoprotein profiles provided additional useful clinical information for combined hyperlipidemia (Fredrickson lipoprotein phenotypes IIb, III).